Electrolytic process.



"UNITED STATES PATENT our rcn.

ANSON GARDNER BETTS, or TROY, NEW roux.

I ELECTROLYTIC PROCESS.

v To all whom it may concern:

Be it known that I, Anson GARDNEI, Bn'r'rs, a citizen of the United States, residing at Troy, in the county of Rensselaer, and

; State of New York, have invented certain new and useful Improvements in Electrolytic Processes, of whic the following is a speclfi cation.

This invention relates to electrolytic processes for solutions, in which processes rc ducible compounds are formed at the anode or from the anode products, and it is not dee. sired that they should be again reduced at,

' the cathode.

cathodic reduction in such and at slight cost.

In electrolytic processes for making in soprocesses simply lution reducible substances, for exam 1e al-- 0-. chlorites from the corresponding chlori s, it.

kali and alkaline earth chlorates and is desirable for reasons well-known in the art that no diaphragms should be used, and considerable loss ofthe chlorates etc. produced by the anode reactions generally results from the reducing action of the cathode. I overcome this difiiculty by the use of a cathode'of a metal, preferably of magnesium, not reducible from its compounds at the cathode by the electrolysis of the solution.

I have found 'by experiment that with a cathode of ma nesium in the manufacture of chlorates and y )ochlorites, there is little or no reduction at t e cathode, which I explain by the great oxidizability of the ma nesium superficially, so that-the surface of t e magnesium cathode is always covered with a thin porous layer of the non-conductor, magnesia, probably in hydrated form, which serves as a thin everpresent diaphragm, preventing the contact of more than small portions of the electrolyte and contained reducible compound with the ,aotual cathode surface.

The hydrogen produced, after leavingthe cathode has lost its reducing power, it being a well-known fact that hydrogen in its ordinary state is relatively inactive, as a conse- I quence of which after leaving the cathode surface it bubbles away through the solution untouched.

The objection, above referred to, to diaphragms, disap ears when the diaphragm is thin and is at t e cathode surface itself, and partial success has been claimed for the use of magnesium and calcium salts in the electrolytes, for the purpose of continually pro- Specification of Letters Patent.

. p 1 power. The ob ect of my invention 1s toovercome Patented April 20, 1909.

Application filed December 23, 1908. Serial No. 468,976.

ducing-a film of insoluble hydroxid at the cathode, but this plan is not eflicient'and is much less perfect'in its action than is that of a magnesium cathode, for instance, probably for such reasons as the following.

The film forming on the cathode by oxidation in my method is probably thinner and harder and more strongly attached, hardly breaking away at all, while the de osited film in the old method adheres to t e cathode very little or not at all, so that it is continually exposing the latinum, iron, carbon or other cathode wit By my method it is not necessary to'have any salts of magnesium, calcium etc. in the solution, so that none of. the current is used for the decomposition of such salts.

My method is es ecially useful in the production of hypochlbrites' for bleaching pur poses, having the advantage over the well- ;nown process using the addition of .chromates for the purpose of securinghigh cur rent efficiency, of producing a colorless solution.

In trying to make hypochlorites with a cathode of aluminum, which is almost as oxidizable as magnesium, I found that the caustic generated at the cathode dissolved the aluminum rapidly, and the loss of aluminum was found to be very great in contrast to magnesium, of which the hydroxid is not soluble in caustic solutions.

- I do not believe that it is necessary that the cathode used in practicing my invention should consist of a single elementary substance in a pure state. Obviously an alloy which oxidizes in the solution with the production of'an irreducible coating, not a conits' strong reducing ductor of electricity, might also serve, and

operate without serious reduction of the reducible compounds in-the solution, for ,the-

same reason as pointed out in the case of electrolytic oxidation taining an oxidizable compound with a cathode oxidiaable in contact with the solution cathode.

with the roduction of a coatingmnreduced by electro ysis of the solution.

2. The process of oxidizin a compound in solution which consists in e ectrolyz'ing the solution with a cathode which oxidizes with the production of a coating not reduced by the electrolysis, and insoluble in the solution at the cathode.

'3. The process of producing a reducible compound in solution which consists in electrolyzing the solution containing a compound from which said reducible compound 18 produced, with a metallic cathode which oxldizessuperficially with the production of a coating of a non-conductor of electricity, unreduced by the electrolysis of the solution.

4. The process of producing a reducible compound insolution, which consists in electrolyzing the solution containing a compound from which said reducible compound is reduced-with a suitable anode and a cat iode which forms with one of the ions of the solution, a compound irreducible by the electrol, sis of the solution and not soluble in the solution in the neighborhood of the 5. The process of producing a reducible compound in solution, which consists in electrolyzing the solution containing a compound from which said reducible compound is roduced,'with a suitable anode and a catho e of a solution of a halogen com ound with a suit' able anode and a cathode 0 magnesium.

8. The process of producing oxidizing compounds which consists in electrolyzing a solution containing alkali halid with a suitable anode and a cathode of magnesium.

9. The process of producing a reducible compound in solution which consists in elec trolyzing a solution containing a compound from which said reducible compound is produced, with a suitable anode and a cathode of magnesium,

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

ANSON GARDNER BETTS.

Witnesses BENJAMIN STARBUCK, HARRY PERRY. 

